Client protection switch in optical pluggable transceivers activated through fast electrical data squelch

ABSTRACT

Client-side protection systems and methods are implemented by a network element using a fast electrical squelch with a first optical transceiver and a second optical transceiver. A client-side protection method includes detecting a protection switching event affecting one or more lanes associated with the first optical transceiver; causing a fast electrical squelch to the affected one or more lanes of the first optical transceiver to provide a Loss of Signal (LOS) thereto; and subsequent to the LOS to the first electrical transceiver, causing a fast electrical squelch to corresponding one or more lanes of the second optical transceiver to enable the corresponding one or more lanes thereon.

FIELD OF THE DISCLOSURE

The present disclosure generally relates to optical networking systemsand methods. More particularly, the present disclosure relates to clientprotection switching in optical pluggable transceivers, such as QuadSmall Form-factor Pluggable (QSFP) and variants thereof, 100GForm-factor Pluggable (CFP) and variants thereof, etc., activatedthrough a fast electrical data squelch.

BACKGROUND OF THE DISCLOSURE

In optical networking, optical interfaces can be realized throughoptical pluggable transceivers which are defined via MultisourceAgreements (MSAs), such as QSFP and variants thereof, CFP and variantsthereof, etc. These pluggable transceivers can be used by networkinghardware, such as switches, routers, etc., to form protectedbi-directional links. For example, pluggable transceivers can beincluded in a network element to provide protected client-sideconnectivity. There are various types of client-side optical protection,such as Y-cable protection, Optical 1+1 via an Optical Protection Switch(OPS), etc. Disadvantageously, some MSA transceivers, such as QSFP andvariants thereof, lack a transmitter (Tx) disable pin. Specifically, asthe size of these transceivers decreases, there is less available spacefor pins, such as a Tx disable pin. Without such a pin, turning thetransceiver Tx on and off is a slow process, e.g. hundreds ofmilliseconds, which is unacceptable from a time perspective in anyprotection scheme. Other types of MSAs do define a Tx disable pin, suchas SFP+, XFP, and CFP and variants thereof. However, the implementationhere does not provide a mechanism to disable/enable individual lanes.For example, the Tx disable pin in CFP would control all lanes which isinflexible for transceivers carrying multiple clients, N×M (e.g., 4×100,4×25, 10×10, etc.).

There is a need to support fast client-side protection switch in opticalpluggable transceivers in a manner fully supported by host devices tothe associated specifications.

BRIEF SUMMARY OF THE DISCLOSURE

In an exemplary embodiment, a client-side protection method implementedby a network element using a fast electrical squelch with a firstoptical transceiver and a second optical transceiver includes detectinga protection switching event affecting one or more lanes associated withthe first optical transceiver; causing a fast electrical squelch to theaffected one or more lanes of the first optical transceiver to provide aLoss of Signal (LOS) thereto; and subsequent to the LOS to the firstelectrical transceiver, causing removal of a fast electrical squelchfrom corresponding one or more lanes of the second optical transceiverto enable the corresponding one or more lanes thereon. The fastelectrical squelch can be performed in less than 10 ms to either of thefirst optical transceiver and the second optical transceiver. The firstoptical transceiver and the second optical transceiver can becommunicatively coupled to a host device via a Y-cable device. The firstoptical transceiver and the second optical transceiver can becommunicatively coupled to a host device via an Optical ProtectionSwitching (OPS) device. The first optical transceiver and the secondoptical transceiver can be compliant to a Quad Small Form-factorPluggable (QSFP) variant. The fast electrical squelch can be utilized inlieu of commands over an Inter-Integrated Circuit (I2C) in the QSFPvariant. The first optical transceiver and the second opticaltransceiver can be compliant to a 100G Form-factor Pluggable (CFP)variant. The fast electrical squelch can be utilized in lieu of atransmitter disable pin in the CFP variant.

In another exemplary embodiment, a network element using a fastelectrical squelch for client-side protection thereon includes a firstclient optical transceiver; a second client optical transceiver; and oneor more line optical transceivers adapted to provide working lines andprotect lines for associated lanes from the first client opticaltransceiver and the second client optical transceiver, wherein thenetwork element is adapted to detect a protection switching event on theone or more line optical transceivers affecting one or more lanesassociated with the first client optical transceiver, cause a fastelectrical squelch to the affected one or more lanes of the first clientoptical transceiver to provide a Loss of Signal (LOS) thereto, and,subsequent to the LOS to the first electrical transceiver, cause removalof a fast electrical squelch from corresponding one or more lanes of thesecond client optical transceiver to enable the corresponding one ormore lanes thereon. The fast electrical squelch can be performed in lessthan 10 ms to either of the first client optical transceiver and thesecond client optical transceiver. The first client optical transceiverand the second client optical transceiver can be communicatively coupledto a host device via a Y-cable device. The first client opticaltransceiver and the second client optical transceiver can becommunicatively coupled to a host device via an Optical ProtectionSwitching (OPS) device. The first client optical transceiver and thesecond client optical transceiver can be compliant to a Quad SmallForm-factor Pluggable (QSFP) variant. The fast electrical squelch can beutilized in lieu of commands over an Inter-Integrated Circuit (I2C) inthe QSFP variant. The first client optical transceiver and the secondclient optical transceiver can be compliant to a 100G Form-factorPluggable (CFP) variant. The fast electrical squelch can be utilized inlieu of a transmitter disable pin in the CFP variant.

In a further exemplary embodiment, a pluggable optical transceiveradapted to implement a fast electrical squelch on one or more transmitlanes includes a plurality of receiver optics; a plurality oftransmitter optics; and a host interface communicatively coupledelectrically to the plurality of receiver optics and the plurality oftransmitter optics and coupled electrically via a plurality of pins to ahost device; wherein the plurality of pins include a plurality oftransmitter data pins, and wherein, responsive to detection by a networkelement housing the pluggable optical transceiver of a protectionswitching event affecting one or more active lanes associated withcorresponding transmitter data pins, the pluggable optical transceiveris adapted to detect a fast electrical squelch to the correspondingtransmitter data pins to provide a Loss of Signal (LOS) thereto and toturn off the corresponding plurality of transmitter optics basedthereon. Responsive to detection by the network element housing thepluggable optical transceiver of a protection switching event affectingone or more inactive lanes associated with corresponding transmitterdata pins, the pluggable optical transceiver is adapted to detect a fastelectrical squelch removal from the corresponding transmitter data pinsto provide a data thereto and to turn on the corresponding plurality oftransmitter optics based thereon. The pluggable optical transceiver canbe compliant to a Quad Small Form-factor Pluggable (QSFP) variant. Thepluggable optical transceiver can be compliant to a 100G Form-factorPluggable (CFP) variant.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is illustrated and described herein withreference to the various drawings, in which like reference numbers areused to denote like system components/method steps, as appropriate, andin which:

FIG. 1 is a block diagram of a Quad Small Form-factor Pluggable (QSFP)module in a host device;

FIG. 2 is a schematic diagram of pins on the QSFP module;

FIG. 3 is a block diagram of a 100G Form-factor Pluggable (CFP) module;

FIG. 4 is a network diagram of a network implementing Y-cableprotection;

FIG. 5 is a network diagram of a network implementing Optical ProtectionSwitching (OPS) protection; and

FIG. 6 is a flowchart of a client-side protection process using a fastelectrical squelch.

DETAILED DESCRIPTION OF THE DISCLOSURE

Again, in various exemplary embodiments, the present disclosure relatesto client protection switching in optical pluggable transceivers, suchas Quad Small Form-factor Pluggable (QSFP) and variants thereof, 100GForm-factor Pluggable (CFP) and variants thereof, etc., activatedthrough a fast electrical data squelch. The fast electrical data squelchis used to implement fast client-side protection on pluggabletransceivers for individual lanes. The client-side protection caninclude Y-cable protection, Optical Protection Switch (OPS) protection,etc. The fast electrical data squelch is used to implement a fast turnon and off of client transmitter lanes, e.g., the fast electrical datasquelch is applied to turn off a lane while the fast electrical datasquelch is removed to turn on a lane. Advantageously, the fastelectrical data squelch enables less than 50 ms protection switching (oralternatively 60 ms protection switching with 10 ms to detect and 50 msto switch, or any other value for protection switching less than 400ms), a requirement for client-side protection, with the fast electricaldata squelch turn on and turn off time less than about 10 ms andpreferably less than 5 ms.

Quad Small Form-Factor Pluggable (QSFP)

Referring to FIGS. 1 and 2, in an exemplary embodiment, a block diagramillustrates a QSFP module 10 in a host device 12 and a schematic diagramillustrates pins 14 on the QSFP module 10. The QSFP module 10 is acompact, hot-pluggable transceiver used for data communicationsapplications. The form factor and electrical interface are specified bya multi-source agreement (MSA) under the auspices of the Small FormFactor (SFF) Committee. The QSFP module 10 interfaces networkinghardware to a fiber optic cable or active or passive electrical copperconnection. QSFP module 10 is an industry format jointly developed andsupported by many network component vendors.

The host device 12 can be a router, switch, or any other type ofnetworking or computing device. The host device 12 can include anApplication Specific Integrated Circuity (ASIC) 16 as aSerializer/Deserializer (SERDES) which is electrically connected to ahost edge card connector 18. The host edge card connector 18electrically and mechanically connects to a module card edge 20 which isa host interface. The host edge card connector 18 and the module cardedge 20 include electrical connections such as the pins 14. The QSFPmodule 10 includes one or more receivers 22 which provide a Rx OUT p(p=non-inverted data output) and a Rx OUT n (n=inverted data output)from received optical signal(s) to the host device 12. The QSFP module10 includes one or more transmitters 24 which receive a Tx IN p(p=non-inverted data input) and a Tx IN n (n=inverted data input) fromthe host device and output transmit optical signal(s). The QSFP module10 includes an optical connector/port 26 which provides opticalinterfaces, such as for four channels (Tx 1, Rx 1, etc.).

The QSFP module 10 is available with a variety of transmitter andreceiver types, allowing users to select the appropriate transceiver foreach link to provide the required optical reach over the availableoptical fiber type (e.g., multi-mode fiber or single-mode fiber). TheQSFP module 10 is commonly available in several different categories.For example, 4×4 Gbit/s QSFP has four channels carrying GigabitEthernet, 4GFC (Fiber Channel), or DDR InfiniBand. 4×10 Gbit/s QSFP+ isan evolution of QSFP to support four 10 Gbit/sec channels carrying 10Gigabit Ethernet, 10 GFC Fiber Channel, or QDR InfiniBand. The 4channels can also be combined into a single 40 Gigabit Ethernet link.4×14 Gbit/s QSFP+ (QSFP14) is designed to carry FDR InfiniBand andSAS-3. 4×28 Gbit/s QSFP+ (QSFP28) is designed to carry 100 GigabitEthernet or EDR InfiniBand. This transceiver type is also used withdirect-attach breakout cables to adapt a single 100GbE port to fourindependent 25 gigabit Ethernet ports (QSFP28-to-4x-SFP28).

The QSFP MSA and variants (QSFP+, QSFP28, etc.) defines electricalinterfaces, management interfaces, optical interfaces, mechanicalspecifications and the like for a providing 40G and 100G clients.Specifically, QSFP+ provides four electrical interfaces at 10G (XLPPI,XLAUI, etc) and four optical interfaces at 10G. QSFP28 provides 100G viafour 25G interfaces. QSFP+ is used to carry 40G traffic (40G stripedacross 4 optical lanes running @˜10G each), or 4×10G services with eachfiber carrying an independent 10G service. For example, the QSFP+electrical specifications are defined in SFF-8679 “QSFP+ 4X BaseElectrical Specification” Rev. 1.7, August 2014, the contents of whichare incorporated by reference.

Again, due to the size of the QSFP module 10, there are a limited numberof the pins 14, and as a consequence, the QSFP module 10 (variousvariants) do not have a Tx disable pin. Additionally, the QSFP module 10as well as other module types (e.g., CFP) are often used now formultiple data streams, which may need individual protection. Also,QSFP-DD which is the next generation module being developed for 400GbE,200GbE, Nx100GbE also lacks a Tx Disable pin in the pin definitions.Other module types such as microQSFP, QSFP56, OSFP, and the like areunder development, and will similarly not include a Tx disableelectrical pin. The systems and methods described herein contemplateoperation on any type of pluggable optical transceiver with or without aTx disable electrical pin and with multiple lanes.

To date, Y cable type optical and OPS protection schemes have not beenused with QSFP+/QSFP28 modules due to their failure to meet the timingrequirements. There are two methods to turn off the Tx in the QSFPmodule 10: via the control channel which is an Inter-Integrated Circuit(I2C) and via an optical squelch on the electrical Loss of Signal (LOS).Further, the optical squelch can be implemented in two ways: Averagepower squelch or modulation squelch. Turning off the transmitter throughthe I2C is too slow to meet the client-side protection requirements (<50ms) and a squelch on the electrical LOS is specified to be within 400 msin SFF-8679, again too slow to meet the client-side protectionrequirement.

100G Form-Factor Pluggable (CFP)

Referring to FIG. 3, in an exemplary embodiment, a block diagramillustrates a CFP module 40. The CFP module 40 is a hot-pluggableoptical transceiver form factor enabling 40Gb/s and 100Gb/sapplications, including next-generation High-Speed Ethernet (40GbE and100GbE). The electrical interface may include a nominal signaling lanerate at 10 Gbit/s per lane with various electrical interfacespecifications such as CAUI, XLAUI, OTL4.10, OTL3.4, and STL256.4. Othervariants of CFP may include CFP2 which uses a signaling lane rates of 10Gb/s or 25 Gbit/s per lane and CFP4 which uses a signaling lane rate of25 Gb/s. CFP2 includes options for 10×10 Gb/s electrical signaling(i.e., CAUI) for 100GBASE-SR10, and 4×25 Gb/s electrical signaling(i.e., CAUI-4) for LR4 and ER4 applications. For example, the CFP MSAhas an electrical interface of 4×10G (XLAUI) or 10×10G (CAUI), the CFP2MSA has an electrical interface of 4×25G (CAUI4) or 10×10G (CPPI orCAUI). Another variant of CFP may include CDFP or CFP8 which uses asignaling lane rate of 25 Gbit/s per lane and has an electricalinterface of 16×25G providing 400G (400GAUI-16). CFP8 also supports8×50G electrical interfaces (400GAUI-8).

The CFP module 40 includes various pins 42 which interface to a hostdevice (not shown in FIG. 3). The pins 42 are categorized as ManagementData Input/Output (MDIO, control/alarm, a monitor Rx clock (RXMCLK),receive data (RXDATA), a reference Clock (REFCLK), transmit data(TXDATA), and a monitor Tx Clock (TXMCLK). The CFP module 40 includes acontroller 44, interface integrated circuits (ICs) 46, receive optics48, transmit optics 50, an optical demux 52, and an optical mux 54. Thecontroller 44 interfaces the MDIO and control/alarm pins and theinterface integrated circuits 46 interfaces the remaining pins. TheRXDATA and the TXDATA have M lanes (pins). The receive optics 48 and thetransmit optics 50 can include multiple sets of transceivers, e.g., N,which are combined/split such as using Wavelength Division Multiplexing(WDM) via the demux 52 and the mux 54.

The control/alarm pins for the CFP module 40 include a Tx disable pinwhich can be used for fast optical protection. However, as specified inthe CFP specifications, the Tx disable pin turns off and on all of thetransmit optics 50, i.e., all N transmitters. The CFP module 40 does notsupport individual lanes being turned on and off.

Fast Electrical Squelch

In various exemplary embodiments, the systems and methods describedherein implement client-side protection on a pluggable opticaltransceiver (e.g., the QSFP module 10 or variants thereof, the CFPmodule 40 or variants thereof) using a fast electrical squelch as anLOS. The fast electrical squelch includes a fast turn off or turn on ofelectrical signaling on the associated Tx data pins for the QSFP module10 and the CFP module 40. The fast electrical squelch is implemented inless than 10 ms and preferably less than 5 ms. That is, by “fast,” thefast electrical squelch is implemented in less than 10 ms and preferablyless than 5 ms. This is considerably faster than the currentspecifications for QSFP which perform an electrical squelch in 400 ms.Further, the fast electrical squelch is implemented per lane, e.g., Tx1, Tx 2, Tx 3, Tx 4. By using electrical LOS to implement the Tx off,the systems and methods can both implement client-side protection forbulk interfaces such as 100GbE in a QSFP28 and implement per laneprotection for pluggables supporting multiple interfaces, such as4×10GbE in a QSFP+, CFP4, etc. This is of increasing importance asdensity improvements are planned through having multiple servicessupported in next generation pluggable modules.

The ability to support a fast electrical squelch is implemented in theQSFP module 10 and the CFP module 40 as well as in the host device 12.Specifically, the host device 12 is configured to provide the fastelectrical squelch to turn off or turn on the associated transmitter,such as based on a protection switching event. The QSFP module 10 andthe CFP module 40 are also configured to detect the fast electricalsquelch and to turn off or turn on the corresponding transmitter. Note,the QSFP module 10 and the CFP module 40 can operate in the host device12 whether or not the host device 12 supports the fast electricalsquelch. Thus, the modification of the QSFP module 10 and the CFP module40 to support the fast electrical squelch is backward compatible withany host device 12 supporting the associated standards, even if the hostdevice 12 does not support the fast electrical squelch.

Y-Cable Optical Protection With Fast Electrical Squelch

Referring to FIG. 4, in an exemplary embodiment, a network diagramillustrates a network 100 a implementing Y-cable protection. Y-cableprotection provides line-side protection for a single client interface102 (labeled as client interfaces 102 a, 102 b) in a host device 104(labeled as host devices 104 a, 104 b). Y-cable protection is referredto as “Y-cable” since a cable between the host device 104 and a WDMnetwork element 106 (labeled as network elements 106 a, 106 b) includesa single cable fanning out to dual cables. Y-cable protection includes aY-cable device 108 (labeled as Y-cable device 108 a, 108 b) whichincludes a combiner and a splitter. Y-cable protection is also referredto as Transponder Protection Tray (TPT) by Ciena Corporation. The WDMnetwork elements 106 a, 106 b each can include client interfaces 110(labeled as client interfaces 110 a, 110 b, 110 c, 110 d) and lineinterfaces 112 (labeled as line interfaces 112 a, 112 b, 112 c, 112 d).The line interfaces 112 connect to one another over an optical network114, providing a working and protected path extending between the clientinterface 110 a to the client interface 110 c and between the clientinterface 110 b and the client interface 110 d, respectively. Thus, thehost device 104 with the client interface 102 has line protection in theoptical network 114.

The host device 104 can be a router, switch, or any other type ofnetworking or computing device. The client interface 102 and the clientinterfaces 110 can be the QSFP module 10, the CFP module 40, etc. Sinceclient-side protection, such as using the Y-cable protection, requiresfast switching (e.g., <50 ms), the client interface 102 and the clientinterfaces 110 are configured to support the fast electrical squelch toturn off and turn on individual lanes on the client interfaces 110, in afast manner (e.g., <10 ms and preferably <5 ms).

In the example of FIG. 4, the client interface 102 has a singleinterface which is provided to a Y-cable device 108. The Y-cable device108 a is configured to split an output of the client interface 102 ainto the client interfaces 110 a, 110 b and to couple the clientinterfaces 110 a, 110 b into a single input to the client interface 102a. That is, the Y-cable device 108 a is configured as a splitterdirectionally from the host device 104 a to the network element 106 aand as a switch that selects one of the outputs from the network element106 a for the client equipment 104 a. The Y-cable device 108 b providessimilar functionality between the client interface 102 b and the clientinterfaces 110 c, 110 d. Y-cable protection provides redundancy forclient interface equipment as well as the line in the optical network114. That is, the Y-cable device 108 protects against facility failuresand failures in the optical network 114, but the Y-cable device 108 doesnot protect against failures in the client interface 102. This is animportant scheme of protection since failures are more likely in theoptical network 114 than in the interface between the host device 102and the network element 106.

With the Y-cable device 108 a, only one of the client interfaces 110 a,110 b should be active at any given time. Specifically, the Y-cabledevice 108 a interface a single transmit signal and a single receivesignal between the client interface 102 a and the client interfaces 110a, 110 b. With the conventional approach to turn on and turn off theclient interfaces 110 a, 110 b, it is not possible to switch between theclient interfaces 110 a, 110 b below 50 ms. In fact, using conventionalapproaches (I2C), the client interfaces 110 a, 110 b switch in severalhundred milliseconds, well above application requirements for Y-cableprotection.

With the systems and methods, the network elements 106 a, 106 b areconfigured to turn on and turn off individual lanes on the clientinterfaces 110 a, 110 b using the fast electrical squelch. The networkelements 106 a, 106 b are configured to detect a protection switchingevent at the line interfaces 112 a, 112 b, 112 c, 112 d. The lineinterfaces 112 a, 112 b, 112 c, 112 d can be WDM transceivers or modemswhich are configured to detect the protection switching event. Theprotection switching event can include, without limitation, Loss ofSignal (LOS), Alarm Indication Signal (AIS), Loss of Frame (LOF), HighBit Error Rate (BER), manual switch, or the like. That is, theprotection switching event can be any event used in WDM to implement aswitch between working and protect lines. The WDM network elements 106can utilize any protocol such as, without limitation, Optical TransportNetwork (OTN), or the like.

Assume for illustration purposes the working line is active between theclient interfaces 110 a, 110 c and the protect line is inactive betweenthe client interfaces 110 b, 110 d. The WDM network elements 106 a, 106b are configured to detect the protection switching event affecting oneor more lanes of the client interfaces 110 a, 110 c and tocorrespondingly implement a fast electrical squelch on the affectedlanes to turn off the client interfaces 110 a, 110 c with the protectionswitching event and to turn the corresponding lanes on the clientinterfaces 110 b, 110 d. Note, the fast electrical squelch is performedin a coordinated manner, such as through a bus 118 between the clientinterfaces 110 a, 110 b and between the client interfaces 110 c, 110 d.Specifically, the network element 106 a would turn off the clientinterface 110 a and then turn on the client interface 110 b, such thatneither is active simultaneously to the Y-cable device 108 a. With thefast electrical squelch in or below the 5-10 ms range, the turn off andthe turn on can be implemented well below 50 ms, supporting theassociated protection switching timing requirements.

OPS Optical Protection With Fast Electrical Squelch

Referring to FIG. 5, in an exemplary embodiment, a network diagramillustrates a network 100 b implementing Optical Protection Switching(OPS) protection. The network 100 b is similar to the network 100 a withthe Y-cable device 108 a, 108 b replaced with an OPS 120 (labeled as OPS120 a, 120 b). The Y-cable device 108 a, 108 b is an all-passiveprotection switching device which combines and splits signals to theclient interface 102 and the network element 106 a is responsible forensuring a single active client interface 110 a, 110 b. The OPS 120, onthe other hand, performs active switching. The OPS 120 on the transmitside (110 a & 110 b ingress direction) includes a splitter which splitsthe input transmit signal to two directions, e.g., between the clientinterface 102 a to the client interfaces 110 a, 110 b. On the receiveside (110 a & 110 b egress direction), the OPS 120 includes an active1×2 switch which monitors inputs, such as via a Photodetector (PD), andmaintains the switch based on the monitored inputs. For example, themonitored inputs can be based on power thresholds, BER, etc. In thismanner, the client interface 102 a always transmits to both of theclient interfaces 110 a, 110 b, but only receives an input from one ofthe client interfaces 110 a, 110 b based on the current configuration ofthe switch in the OPS 120.

Individual Lane Fast Electrical Squelch

The optical network 114 is moving towards decoupling optical channels(wavelengths) from logical channels, such as in ITU-T RecommendationG.709 “Interfaces for the optical transport network” (06/2016), thecontents of which are incorporated by reference, which describes the useof multiple optical carriers for a single digital transport interface inline side applications, such as an Optical Transport Unit-Cn (OTUCn)which is carried via multiple Optical Tributary Signal (OTSi) carriers(lambdas). Thus, there is no longer necessarily a correlation in theoptical network 114 between the data from the client interfaces 110 anda protection switching event may not affect all of the lanes on theclient interfaces 110. In this manner, the systems and methods canprovide LOS to individual lanes as opposed to all lanes simultaneouslyas is the case in convention CFPs and the like with a single Tx disablepin. This individual lane approach can be used in any pluggabletransceiver including QSFP, CFP, etc.

Client-Side Protection Process Using Fast Electrical Squelch

Referring to FIG. 6, in an exemplary embodiment, a flowchart illustratesa client-side protection process 200 using a fast electrical squelch.The client-side protection process 200 can be implemented by a networkelement, such as the network element 106 in the networks 100 a, 100 b.The client-side protection process 200 includes detecting a protectionswitching event affecting one or more lanes associated with the firstoptical transceiver (step 202); causing a fast electrical squelch to theaffected one or more lanes of the first optical transceiver to provide aLoss of Signal (LOS) thereto (step 204); and, subsequent to the LOS tothe first electrical transceiver, causing removal of a fast electricalsquelch from corresponding one or more lanes of the second opticaltransceiver to enable the corresponding one or more lanes thereon (step206). The fast electrical squelch can be performed in less than 10 ms toeither of the first optical transceiver and the second opticaltransceiver.

Optionally, the first optical transceiver and the second opticaltransceiver can be communicatively coupled to a host device via aY-cable device. Alternatively, the first optical transceiver and thesecond optical transceiver can be communicatively coupled to a hostdevice via an Optical Protection Switching (OPS) device. The firstoptical transceiver and the second optical transceiver can be compliantto a Quad Small Form-factor Pluggable (QSFP) variant. The fastelectrical squelch can be utilized in lieu of commands over anInter-Integrated Circuit (I2C) in the QSFP variant. The first opticaltransceiver and the second optical transceiver can be compliant to a100G Form-factor Pluggable (CFP) variant. The fast electrical squelchcan be utilized in lieu of a transmitter disable pin in the CFP variant.

In another exemplary embodiment, a network element using a fastelectrical squelch for client-side protection thereon includes a firstclient optical transceiver; a second client optical transceiver; and oneor more line optical transceivers adapted to provide working lines andprotect lines for associated lanes from the first client opticaltransceiver and the second client optical transceiver, wherein thenetwork element is adapted to detect a protection switching event on theone or more line optical transceivers affecting one or more lanesassociated with the first client optical transceiver, cause a fastelectrical squelch to the affected one or more lanes of the first clientoptical transceiver to provide a Loss of Signal (LOS) thereto, and,subsequent to the LOS to the first electrical transceiver, cause removalof a fast electrical squelch from corresponding one or more lanes of thesecond client optical transceiver to enable the corresponding one ormore lanes thereon.

In a further exemplary embodiment, a pluggable optical transceiveradapted to implement a fast electrical squelch on one or more transmitlanes includes a plurality of receiver optics; a plurality oftransmitter optics; and a host interface communicatively coupledelectrically to the plurality of receiver optics and the plurality oftransmitter optics and coupled electrically via a plurality of pins to ahost device; wherein the plurality of pins include a plurality oftransmitter data pins, and wherein, responsive to detection by a networkelement housing the pluggable optical transceiver of a protectionswitching event affecting one or more active lanes associated withcorresponding transmitter data pins, detecting a fast electrical squelchto the corresponding transmitter data pins to provide a Loss of Signal(LOS) thereto and to turn off the corresponding plurality of transmitteroptics based thereon. Responsive to detection by the network elementhousing the pluggable optical transceiver of a protection switchingevent affecting one or more inactive lanes associated with correspondingtransmitter data pins, detecting a fast electrical squelch removal fromthe corresponding transmitter data pins to provide a data thereto and toturn on the corresponding plurality of transmitter optics based thereon.

It will be appreciated that some exemplary embodiments described hereinmay include one or more generic or specialized processors (“one or moreprocessors”) such as microprocessors; Central Processing Units (CPUs);Digital Signal Processors (DSPs): customized processors such as NetworkProcessors (NPs) or Network Processing Units (NPUs), Graphics ProcessingUnits (GPUs), or the like; Field Programmable Gate Arrays (FPGAs); andthe like along with unique stored program instructions (including bothsoftware and firmware) for control thereof to implement, in conjunctionwith certain non-processor circuits, some, most, or all of the functionsof the methods and/or systems described herein. Alternatively, some orall functions may be implemented by a state machine that has no storedprogram instructions, or in one or more Application Specific IntegratedCircuits (ASICs), in which each function or some combinations of certainof the functions are implemented as custom logic or circuitry. Ofcourse, a combination of the aforementioned approaches may be used. Forsome of the exemplary embodiments described herein, a correspondingdevice in hardware and optionally with software, firmware, and acombination thereof can be referred to as “circuitry configured oradapted to,” “logic configured or adapted to,” etc. perform a set ofoperations, steps, methods, processes, algorithms, functions,techniques, etc. on digital and/or analog signals as described hereinfor the various exemplary embodiments.

Moreover, some exemplary embodiments may include a non-transitorycomputer-readable storage medium having computer readable code storedthereon for programming a computer, server, appliance, device,processor, circuit, etc. each of which may include a processor toperform functions as described and claimed herein. Examples of suchcomputer-readable storage mediums include, but are not limited to, ahard disk, an optical storage device, a magnetic storage device, a ROM(Read Only Memory), a PROM (Programmable Read Only Memory), an EPROM(Erasable Programmable Read Only Memory), an EEPROM (ElectricallyErasable Programmable Read Only Memory), Flash memory, and the like.When stored in the non-transitory computer readable medium, software caninclude instructions executable by a processor or device (e.g., any typeof programmable circuitry or logic) that, in response to such execution,cause a processor or the device to perform a set of operations, steps,methods, processes, algorithms, functions, techniques, etc. as describedherein for the various exemplary embodiments.

Although the present disclosure has been illustrated and describedherein with reference to preferred embodiments and specific examplesthereof, it will be readily apparent to those of ordinary skill in theart that other embodiments and examples may perform similar functionsand/or achieve like results. All such equivalent embodiments andexamples are within the spirit and scope of the present disclosure, arecontemplated thereby, and are intended to be covered by the followingclaims.

1. A client-side protection method implemented by a network elementusing a fast electrical squelch with a first optical transceiver and asecond optical transceiver, the client-side protection methodcomprising: detecting a protection switching event on a client sideaffecting one or more lanes associated with the first opticaltransceiver; causing a fast electrical squelch to turn off the affectedone or more lanes of the first optical transceiver to provide a Loss ofSignal (LOS) thereto; and subsequent to the LOS to the first electricaltransceiver, causing removal of a fast electrical squelch fromcorresponding one or more lanes of the second optical transceiver toenable the corresponding one or more lanes thereon.
 2. The client-sideprotection method of claim 1, wherein the fast electrical squelch isperformed in less than 10 ms to either of the first optical transceiverand the second optical transceiver.
 3. The client-side protection methodof claim 1, wherein the first optical transceiver and the second opticaltransceiver are communicatively coupled to a host device via a Y-cabledevice.
 4. The client-side protection method of claim 1, wherein thefirst optical transceiver and the second optical transceiver arecommunicatively coupled to a host device via an Optical ProtectionSwitching (OPS) device.
 5. The client-side protection method of claim 1,wherein the first optical transceiver and the second optical transceiverare compliant to a Quad Small Form-factor Pluggable (QSFP) variant. 6.The client-side protection method of claim 5, wherein the fastelectrical squelch is utilized in lieu of commands over anInter-Integrated Circuit (I2C) in the QSFP variant.
 7. The client-sideprotection method of claim 1, wherein the first optical transceiver andthe second optical transceiver are compliant to a 100G Form-factorPluggable (CFP) variant.
 8. The client-side protection method of claim7, wherein the fast electrical squelch is utilized in lieu of atransmitter disable pin in the CFP variant.
 9. A network element using afast electrical squelch for client-side protection thereon, the networkelement comprising: a first client optical transceiver; a second clientoptical transceiver; and one or more line optical transceivers adaptedto provide working lines and protect lines for associated lanes from thefirst client optical transceiver and the second client opticaltransceiver, wherein the network element is adapted to detect aprotection switching event on a client side of the one or more lineoptical transceivers affecting one or more lanes associated with thefirst client optical transceiver, cause a fast electrical squelch toturn off the affected one or more lanes of the first client opticaltransceiver to provide a Loss of Signal (LOS) thereto, and subsequent tothe LOS to the first electrical transceiver, cause removal of a fastelectrical squelch from corresponding one or more lanes of the secondclient optical transceiver to enable the corresponding one or more lanesthereon.
 10. The network element of claim 9, wherein the fast electricalsquelch is performed in less than 10 ms to either of the first clientoptical transceiver and the second client optical transceiver.
 11. Thenetwork element of claim 9, wherein the first client optical transceiverand the second client optical transceiver are communicatively coupled toa host device via a Y-cable device.
 12. The network element of claim 9,wherein the first client optical transceiver and the second clientoptical transceiver are communicatively coupled to a host device via anOptical Protection Switching (OPS) device.
 13. The network element ofclaim 9, wherein the first client optical transceiver and the secondclient optical transceiver are compliant to a Quad Small Form-factorPluggable (QSFP) variant.
 14. The network element of claim 13, whereinthe fast electrical squelch is utilized in lieu of commands over anInter-Integrated Circuit (I2C) in the QSFP variant.
 15. The networkelement of claim 9, wherein the first client optical transceiver and thesecond client optical transceiver are compliant to a 100G Form-factorPluggable (CFP) variant.
 16. The network element of claim 15, whereinthe fast electrical squelch is utilized in lieu of a transmitter disablepin in the CFP variant.
 17. A pluggable optical transceiver adapted toimplement a fast electrical squelch on one or more transmit lanes, thepluggable optical transceiver comprising: a plurality of receiveroptics; a plurality of transmitter optics; and a host interfacecommunicatively coupled electrically to the plurality of receiver opticsand the plurality of transmitter optics and coupled electrically via aplurality of pins to a host device; wherein the plurality of pinscomprises a plurality of transmitter data pins, and wherein, responsiveto detection by a network element housing the pluggable opticaltransceiver of a protection switching event on a client side affectingone or more active lanes associated with corresponding transmitter datapins, the pluggable optical transceiver is adapted to detect a fastelectrical squelch to the corresponding transmitter data pins from thenetwork element to provide a Loss of Signal (LOS) thereto and to turnoff the corresponding plurality of transmitter optics based thereon. 18.The pluggable optical transceiver of claim 17, wherein, responsive todetection by the network element housing the pluggable opticaltransceiver of a protection switching event affecting one or moreinactive lanes associated with corresponding transmitter data pins, thepluggable optical transceiver is adapted to detect a fast electricalsquelch removal from the corresponding transmitter data pins to providea data thereto and to turn on the corresponding plurality of transmitteroptics based thereon.
 19. The pluggable optical transceiver of claim 17,wherein the pluggable optical transceiver is compliant to a Quad SmallForm-factor Pluggable (QSFP) variant.
 20. The pluggable opticaltransceiver of claim 17, wherein the pluggable optical transceiver iscompliant to a 100G Form-factor Pluggable (CFP) variant.